GB1099871A - Improvements in or relating to a method and apparatus for printing legible characters - Google Patents

Abstract

1,099,871. High speed selective printing. ROBERT BOSCH G.m.b.H. March 1, 1965 [March 13, 1964], No. 8608/65. Heading B6F. Ink-less printing; characters formed by an assembly of dots.-A method of printing characters from a row of electrodes selectively energized as a metal coated insulating material record carrier is fed past them, comprises applying a voltage of 20-50 v. so that the resilient free ends of the electrodes vaporize the metal layer to form the characters. In Fig. 1 (not shown), the carrier is a tape fed longitudinally past a row of seven electrodes and the characters are formed as the tape moves. In Fig. 3 (not shown) the method is applied to a line printer. An erodable sheet 23 is attached to a platen so that a single printing head 24 moves relatively thereto such that with every full revolution of the platen a line of text is vaporized out of the metal layer of the metal layer of the recording carrier. Multiple character printing.-The method may be applied to line printers where a vaporizing head is in each character position, see Fig. 7 (not shown). Printing heads.-Each printing head comprises a wire 30, Fig. 4 (not shown), mounted at one end on a terminal plate 31. Each plate 31 is separated by an insulating plate 32 and mounted in a housing 34. The free ends project on to the record through apertures in a plate 33. In a modification, Fig. 6 (not shown), the wires are mounted on circular discs which may be adjusted as the ends of the wires wear. Cleaning printing heads.-A jet of air may be introduced into the printing heads which in passing through the apertures in the plate 33 keeps the electrodes clean. In a modification the head is moved away from the record and cleaned by a brush.